“Of course it gave me confidence,” Nava said. “John and Torey have done a great job of communicating with us about whether we’re playing the following day. The opportunity to mentally prepare is huge.”

Asked how much difference that can make, Nava smiled.

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With the afternoon shadows falling on Fenway Park, Nava came to the plate in the seventh inning with the chance to reward Farrell’s faith in him. The Red Sox, stifled all day by Chen, had runners at second and third base and one out in a scoreless game.

Nava drove an inside fastball so far out of the old ballpark that it crossed Lansdowne Street. The shot gave the Red Sox a 3-1 victory before a sellout crowd of 37,008.

Before the game, Farrell said he wanted Nava in the lineup instead of rookie Jackie Bradley Jr. because he has seen improvement in Nava’s plate approach batting righthanded.

“He puts up a consistent at-bat,” said the manager. “Numbers bear it out that he’s had more success lefthanded. But I think just in general he’s been a confident offensive player.”

It was the right button to push. Nava walked, singled, and hit a home run that long will be remembered. He also homered and drove in two runs Sunday.

“It’s been an amazing couple of days,” said Nava, who until this season had never been on an Opening Day roster. “Just to get this chance with this team means a lot to me. When you’re here for the home opener and everything that goes on, that’s pretty special.”

Nava has the humility you would expect from a player who was once cut from his college team and became an equipment manager. But as he watched the ball fly, he flipped his bat just a little and pumped his fist as the crowd roared.

The Red Sox have won nine consecutive home openers, the longest active streak in the majors. More importantly, they are 5-2 and playing the way Farrell hoped they would when spring training started.

“I know he’s pleased with how things are going,” Lovullo said. “Guys are playing hard, the energy has been positive. The way we’re going about our business has been the way we all wanted.”

It’s a common theme around the Sox. After a year of living dangerously under former manager Bobby Valentine, the Sox have a sense of direction under Farrell.

“He trusts all of us,” said second baseman Dustin Pedroia, who started the winning rally by reaching on an infield single before Mike Napoli doubled. “I’ve known him for a while and John has always been great to me.

“He’s done a great camp. Spring training was awesome and the way we started has been good. It’s only seven games and we’ve got to keep it going.”

It’s evident, too, that Farrell and pitching coach Juan Nieves have drawn out the talent in their rotation. Clay Buchholz (2-0) threw seven shutout innings against the Orioles, allowing only three singles. He struck out eight and walked four.

Buchholz put runners on base in every inning but the sixth. But the Orioles were 1 for 14 with runners on against the righthander.

“I actually felt better pitching out of the stretch today,” said Buchholz. “I felt like the tempo was better.

“Obviously, you don’t want runners on base, because that leads to multiple things. But being able to sort of slow the game down in that way in taking some moving parts out of it and being set over the rubber and throwing pitches.”

The Sox are undefeated in the four games started by Buchholz and No. 1 starter Jon Lester. The two have allowed three earned runs over 26 innings.

Red Sox starters have a 2.45 earned run average with 47 strikeouts over 40⅓ innings.

“You’ve got to keep everything on an even keel, I think,” said Buchholz. “Try not to get too high, don’t get overconfident with it. Just go out and do your work. That’s sort of where I’m going to leave it.”

Andrew Bailey and Joel Hanrahan closed the game out. Bailey overpowered the Orioles in the eighth inning, striking out two. Hanrahan allowed two hits in the ninth inning, one a solo home run by Adam Jones. But that was a footnote on an otherwise perfect day for the Sox.

Farrell was just happy to be among friendly faces after being jeered for three days by Blue Jays fans still sore that he left Toronto to return to the Red Sox.

“After a weekend of boos, today was really good,” Farrell said. “To come away with a win as clean as we played, as well as we pitched . . . this team is growing in confidence by the day.”